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Silibinin (SIL), the most active phytocompound from Silybum marianum (L.), exerts many biological effects but has low stability and bioavailability. To overcome these drawbacks, the current research proposed the synthesis of silibilin oleate (SIL-O) and silibilin linoleate (SIL-L) derivatives as prodrugs with potentially optimized properties for biomedical applications, and the establishment of their in vitro-in ovo safety profiles. The physicochemical characterization of the obtained compounds using density functional theory (DFT) calculations, and Raman and 1H liquid-state nuclear magnetic resonance (NMR) spectroscopy confirmed the formation of SIL-O and SIL-L complexes. Computational predictions revealed that these lipophilic derivatives present a lower drug-likeness score (-29.96 for SIL-O and -23.55 for SIL-L) compared to SIL, but an overall positive drug score (0.07) and no risk for severe adverse effects. SIL-O and SIL-L showed no cytotoxicity or impairment in cell migration at low concentrations, but at the highest concentration (100 µM), they displayed distinct toxicological profiles. SIL-L was more cytotoxic (on cardiomyoblasts - H9c2(2-1), hepatocytes - HepaRG, and keratinocytes - HaCaT) than SIL-O or SIL, significantly inhibiting cell viability (< 60%), altering cellular morphology, reducing cell confluence (< 70%), and inducing prominent apoptotic-like nuclear features. At the concentration of 100 µM, SIL-O presented an irritation score (IS) of 0.61, indicating a lack of irritant effect on the chorioallantoic membrane (CAM), while SIL-L was classified as a slight irritant with an IS of 1.99. These findings outline a more favorable in vitro and in ovo biocompatibility for SIL-O compared to SIL-L, whose applications are dosage-limited due to potential toxicity.

The article extends the theoretical and applicative analysis of Zipf’s law. We are concerned with a set of properties of Zipf’s law that derive directly from the power law expression and from the discrete nature of the objects to which the law is applied, when the objects are words, lemmas, and the like. We also search for variations of Zipf’s law that can help explain the noisy results empirically reported in the literature and the departures of the empirically obtained nonlinear graph from the theoretical linear one, with the variants analyzed differing from Mandelbrot and lognormal distributions. A problem of interest that we deal with is that of mixtures of populations obeying Zipf’s law. The last problem has relevance in the analysis of texts with words with various etymologies. Computational aspects are also addressed.

In the present study we established for the “Nonconventional Technologies” research field, the composition of a keyword vector (terms specific to the analyzed field) = {advanced materials, electrical-discharge machining, hybrid machining, electrochemical machining, micro EDM, micro-ECM, hybrid ultrasonic machining} to carry out a research based on two main directions/components. The first component consists in the process of identifying the works that address the specific terms in the composition of the above vector in Web of Science. The second component is the analysis of the interest of Google users, in searches based on the keyword vector. The emergence, development and diversification of the technologies that make up the keyword vector in this paper is mainly due to their use in the processes of advanced materials machining. The importance, and the key role played by advanced materials and technologies is emphasized by utmost personalities from the academic, research and industry fields.

The unconventional technologies appeared as a result of the unconventional development of the digital economy. The role of the “unconventional technologies” within the knowledge - based economy (more or less conventional) includes, among the specialists, the existence of the unconventional thinking. The main results of this thinking way are to be found in important scientific papers, such as the ones from the Web of Science data bases. The present paper includes an analysis of the scientific papers existed in the Web of Science data bases and its topic is “unconventional technologies”. The case study is focused on two periods of time: 1975-2019 and 2015-2019, as part of the economy based on knowledge. The analysis of Web of Science data was accomplished by grouping the data both regarding the topic and the countries/regions.

The article extends the theoretical and applicative analysis of Zipf's law. We are concerned with a set of properties of Zipf's law that derive directly from the power law expression and from the discrete nature of the objects to which the law is applied, when the objects are words, lemmas, and the like. We also search for variations of Zipf's law that can help explain the noisy results empirically reported in the literature and the departures of the empirically obtained nonlinear graph from the theoretical linear one, with the variants analyzed differing from Mandelbrot and lognormal distributions. A problem of interest that we deal with is that of mixtures of populations obeying Zipf's law. The last problem has relevance in the analysis of texts with words with various etymologies. Computational aspects are also addressed. [ABSTRACT FROM AUTHOR]

From a functional perspective, a service is a standalone unit, such as taking a request from an e-commerce site. By this definition, a service is an operation that can be invoked discreetly. Services can be combined to provide the functionality of a high scope software. SOA makes it easier for different software components on computers connected via a network to cooperate in order to accomplish a certain functionality. SOA comprises several dimensions that must work together effectively to be successful. The adoption of service-based technology itself will not allow organizations to achieve benefits associated with SOA.

The paper deals with the testing of a rotary head for ultrasonically aided electrical discharge machining (EDM+US) that can be used at finishing and semifinishing modes and EDM with complex kinematics - “milling EDM”. The rotation movement using of the electrode-tool is justified by the fact that during the EDM process, the energy is dissipated over the machined surface, and thus its roughness is decreased. But this comes also with the higher instability of EDM process, often short-circuits between the tool and the workpiece, and the idle state due to the variable gap. The tool ultrasonic vibrations oriented perpendicular on the frontal machined surface confirmed both roughness and EDM stability improving, and consequently machining rate, at all working modes tested in this research. The curves of roughness and machining rate are presented at different values of tool rotation speed and consumed power on ultrasonic chain. The obtained surface microgeometry was also studied using scanning electron microscope.

The paper deals with a rotary head for ultrasonically aided electrical discharge machining (EDM+US) that can be used at finishing and semifinishing modes and EDM with complex kinematics - “milling EDM”. The rotary movement of the electrode-tool has the advantage that during the discharge duration, the energy is dissipated over the machined surface, and thus it and be levelled, i.e. the roughness is decreased, but the disadvantage of the instability of EDM process that is increased - often short-circuits between the tool and the workpiece. The ultrasonic vibration of the tool has the capacity to increase the stability of the removal process and hence the output EDM technological parameters. The paper presents the construction of the rotary head in two variants. The first one is more compact and more compatible to be used on CNC machining. The second one has an airier construction, which allows a better cooling of the ultrasonic transducer zone, susceptible to be overheated during EDM process.

Regardless of the type and size of the organization in which we operate, it is essential for us to know what solutions to choose in order to use them knowingly and capitalise their potential to the full capacity. Joint reporting, collecting and organizing large data volumes (Big Data) in order to automate and streamline the decision-making are possible by means of Business Intelligence (BI) systems. The use of BI enables the construction and implementation of complementary strategies, whose implicitly result is competitive advantages. This concept was applied in nonconventional technologies, namely electrical discharge machining.